Journal of Korean Society of Transportation ISSN:1229-1366(Print) 2234-4217(Online) 대한교통학회지

It has been an issue to deliver traffic regulation and control information to autonomous vehicles flawlessly from the highway infrastructure to ensure safe driving. Although issues of recognizing and decoding existing roadside devices and their information contents have been highlighted, it has been missing the fact that urban traffic regulation that autonomous vehicles should follow is complex, time and mode dependent, and compound, multiple ununiformed text signs. Recent studies found interests in how to generate, manage, and utilize such complex and compound conditions digitally and handling multiple traffic control devices legally addressed by the national traffic laws. This paper presents a digital communication protocol delivering regulatory information from an Internet-of-things device attached to a conventional traffic control device to autonomous vehicles (D2V). The data can be categorized into two different sets, the basic and the supplemental, and the total size is 32bits, subjected to the current power-supply capacity. The basic contains geographical and management information, and the supplemental contains specific information for regulation, such as indication, direction, weight, time, day, distance, and so on. Five different types of D2V communication protocols were prepared for selective application of those depending on field conditions in practice. It is expected that digital informatization of traffic control devices could introduce progress for a safe autonomous vehicle-highway environment.